mitosis & meiosis Flashcards
Division of somatic cells in eukaryotic organisms. A single cell divides into two identical daughter cells. This maintains the set of 23 chromosomes pair
Mitosis
Refers to the number of sets of chromosomes in cells
Ploidy
One copy of each chromosome. Designated as “n, is 23 (n=23) “ the number of chromosomes in one set. These are gametes.
Haploid
Two sets of chromosomes
designated as “2n, is 46 (2n=46) “
Somatic cells
Diploid
Parts of a chromatid
Short arm
Centromere
Kinetochore
Long Arm
Telomere
Band
This division process is an integral part of the cell cycle, the life of cells from its origin in the division of a parent cell until its own division into two
Cell division
Cell division functions in ______,_____, and ______.
Reproduction, growth, repair
is any biological cell forming the body of a multicellular organism which makes up the connective tissue, skin blood, bones & internal organs
Somatic cell
Have half as many chromosomes as somatic cells, or 23 chromosomes in human
Reproductive cells/ Gametes
Chromosomes are composed of _______ a complex of DNA & Protein; most chromosomes are about ____ DNA and ____ Proteins
Chromatin
40%, 60%
Chromosomes exist in ______ pairs in diploid cells. All other chromosomes (autosomes) have ______
Homologous
Homologues
Set of the arrangement of chromosomes based on shape, size, & length.
Karyotyping
makes up the traits/ characteristics of the other body parts
Autosomes
Identifies the sex identity of the individual as either female or male
Female: XX
Male: XY
Sex Chromosomes
Same length, centromere position, staining patterns
Homologous chromosomes
Two Major Phases of Eukaryotic Cells Cycle
Interphase
Mitosis
Stages of Interphase
Gap 1
Synthesis
Gap 2
this is the stage where a cell grows in size and organelles replicate
Gap 1
this is the stage where DNA is replicated. It forms the mitotic spindle
Synthesis
usually shortest among the three stages. Occurs after the DNA has been replicated but before mitosis begin
Gap 2
Phases of Mitosis
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
Stage of mitosis where spindle fibers form
Prophase
stage of mitosis where chromosomes align along the equator of the cell w/ one chromatid facing each other
Metaphase
Sister chromatids separate. Spindle fibers attached to kinetochores shorten and pull chromatids towards the poles.
Anaphase
Spindle fibers disintegrate. Cytokinesis occurs
Telophase
Animal cells undergo _______ through the formation of a cleavage furrow.
Cytokinesis
Fusion of two gametes to produce a single zygote.
Sexual Reproduction
Restores the diploid condition by combining two haploid sets of chromosomes
Fertilization
It occurs only in specialized cells called germ-line cells
Meiosis
Meiosis divides into _____ unique daughter cells
4
Two divisions of nucleus in Meiosis
Meiosis i & meiosis ii
The phase where the DNA coils tighter, and individual chromosomes first become visible under a light microscope as a matrix of thread. Homologous chromosomes find each other and become closely associated, a process called _____ or _______.
Prophase 1
pairing or synapsis
Chromosomes duplicate in what phase?
Interphase
it is a process that involves a series of events in which the DNA segments are exchanged between nonsister chromatids
Crossing over in Prophase 1
the microtubules of the spindle fibers begin to shorten. homologues are pulled apart but not the sister chromatids.
Anaphase 1
in this phase, the chromosomes have segregated into two clusters
telophase 1
is like a mitotic division without DNA replication
Meiosis ii
produced in the testes of animal cells
Sperm cells
is the process of forming gametes from diploid cells of the germ line.
Gametogenesis
process of forming sperm cells by meiosis in specialized organs known as gonads
Spermatogenesis
process of forming of an ovum by meiosis in specialized gonads known as ovaries
Oogenesis
3 Major stages of cell cycle
Interphase
Mitosis
Cytokinesis
